Shifting mechanism for change gearing



March 24, 1942 7 w, AUER 2,277,198

' SHIFTING MECHANISM FOR CHANGE GEARING Filed Jur xe 19, 1939. 2 Sheets-Sheet 1 Fig. 4

vgw 20 H9? 9 mkw 32 37 35 @JI C W P R zm or March 24, 1942. WAUE R' 2,277,198

SHIFTING MECHANISM FOR CHANGE GEARING Filed June 19, 1959 2 Sheets-Sheet 2 /l i llepm u.er

l'nuenf r Patented Mar. 24, 1942 iUgNlTED STATES PATENT OFF-ICE I Q .Zmussf h A Wilhelm Auer, Heidenheim, Brenz, Germany Germany June 22, 1938 Ap ucaa .iune 19,1939, Serial No. 280,011 7 12 Claims. (Cl. I l- 173) 'This invention relates to change gearing and in particular to devices for shifting such change gearing.

One object of this invention is to pi'ovide mechanism for shifting change gearing to either of two end positions and at the same time to prevent the accidental shifting of the gearing.

Another object is to provide a device for shifting change gearing having a slidable shifting member wherein the shifting member is shifted to and fro by means of a lever having mecha-' nism associated therewith so constructed and arranged as to hold the lever securely in its end positions and to prevent an accidental shifting of the shifting memberby reason .of the fact that any tendency to shift the shifting member operates to set up a component of force which acts in opposition to the shifting of the lever.

Another object is to provide a change gearing Another object is to provide a change gearing with a shifting device as set forth above wherefor locking the apparatus selectively in its end positions or in an intermediate neutral position wherein the driving connection is broken so that the driven shaft.

' in a manually operated locking device is provided no power is transmittedfrom the drive shaft to In the drawings,

Figure 1 is a diagrammatic view partly in section showing a preferred embodiment of the change gearing and shifting device of this-invention. 1

Figure 2 is a longitudinal section taken along the line A-A in Figure 1;

Figure 3 is a fragmentary view of a modification of a portion of the mechanism shown in Figure 1.

Referring to the drawings in detail, Figure 1 shows the change gearing ofthisinvention as embodied in reverse gearing. The drive shaft 9 is connected to a prime mover such as a motor (not shown) and carries a bevel gear I!) meshing with similar bevel gears i2 and i3 loosely mounted upon the driven shaft ll; Keyed orsplined to the drivenshaft H so as to be slidable therealong is a gear shift member l4. having onits opposite ends clutch teeth l5 and I5 engageable with corresponding recesses in the bevel gears l2 or l3. In this manner when the gear'shift'member H is shifted to either of its extreme or end positions a driving connection is established between the drive Shaft'S-and the driven shaft ll through the bevel gear llland one of mounted bevel gears l2 or I3.

The gear shift member this provided with an annular groove Ma which is|engaged by one end of the gear shift lever l8 which is mounted upon the pivot shaft II. The latter'is in turn-suitably supported by the frame of the machine.

Associated with the gear shift lever l8 and serving to actuate the latter is a control lever i9 mounted upon the pivot shaft 20 which in turnis also suitably mounted upon the frame or the "machine. The controlylever H] at one end carriesa pin |9a which is engaged by the ends of the piston rods 2| and 22 *connected to the pressure operated pistons 23 and 24 reciprocable in the cylinders 23a and 24a by means of pressure fluid admitted thereto through the conduits 23b and 24b, respectively.

Mounted on the control lever I9 is a pin 25 which engages a cut-away portion 26 of approximately triangular or heart-shaped form and is located at the opposite end of the gear shift lever i8 from the end which engages the gear shift member M. The engagement of the pin 25 with the cut-a'way portion 26 is such that in one end position the pin 25 lies in the left corner of the cutaway' portion 26 and in the other end position it lies in the right corner thereof. Between these end positions the pin 25 slides relatively to the two sides 21 and 28 which are formed by arcs having the radius R. This radius is struck from the center of the pivot shaft 20 and has a length equal to the distance between the centers of the shaft 20 and pin 25 plus the radius of the pin 25. y

The gear shift-lever l8 and control lever l9 are yieldingly interconnected by a spring device generally designated 29 and consisting of a plunger 29a pivotally mounted upon the pivot shaft l1 and engaging a coil spring 2% within a cylinder-29c mounted upon the pivot pin 29d which in turn is mounted upon one end of the control lever l9. tends to urge the control lever is into one or another of its end positions with the pin 25 coming to rest in theright hand or left hand corner of the cut-away portion 26'.

In order to prevent the pressure pistons 23 and the loosely I I This spring device 29 thus 24 from exerting a. pressure against the bevel gears 12 or l3 through the intermediate mechanism, the gear shift lever i3 is provided with an arcuate slot 30 engaged by a stop pin 3| fixedly mounted upon any suitable portion of the frame of the machine. co-acts with the ends of the arcuate slot 38 to limit the swinging of the gear shift lever 18 to an amount just suflicient to engage the teeth l5 or it of the gear shiftmember l4 with the corresponding recesses in the loosely mounted bevel gears l2 or 13 yet without exerting any end thrust upon the latter.

The control lever 19 is additionally provided with an arm 32 in which ashaft 35 is pivotally mounted and connected with the universal joint 34 to the operating rod 33. The operating rod 33 is limited in its, motion by the annular knife edge "bearing 36 so that the shaft 35 may be rotated manually by means of the operating rod 33 regardless of the positions which the control lever l9 and its arm 32 may occupy at the moment. By this arrangement also the control lever l9 may ,be manually shifted by operating the rod 33 manually in the event of a failure of the pressure fluid employed for operating the pistons 23 and 24. The arm 32 is provided'with a longitudinal bore 32a in which a stop rod 31 is slidably mounted. The stop rod 31 carries a hollow enlargement 31a (Figure 2) reciprocable in the enlarged bore 32?). The opposite end of the stop rod 31 is engageable with corresponding slots or notches 38 arranged at suitable intervals in a-quadrant 39 fixedly mounted upon any suitable part of the machine. By the notches.

38 and stop pin 31 the control lever [8- may be locked in its extreme end positions for forward or' "rearward movement of the apparatus or driven-shaft H as well'as in a middle or neutral position wherein no power will betransmitted from the drive shaft 9 to the driven shaft H.

Thus in the event that the vapparatus'is employed in a vehicle the locking of the mechanism in the middle position enables the vehicle to be towed by an additional power operated vehicle or locomotive in the event that a breakdown of the engine or driving motor occurs in the first mentioned vehicle.-

Mounted upon the shaft :35 is an arm 40 which engages the inner walls of the hollow enlargelution of the shaft 35. In the operation of the shifting mechanism the stop rod 31 is shifted into its unlocking position by rotating the shaft 35 by the manually operated rod 33. The con-V trol lever l9 may then be shifted manually by pushing the rod 33 longitudinally so that it swings the arm 32 around the pivot shaft 20.-

The controlflever l9 and its pin then swing through an arcuate path from one corner to the other-comer of the heart-shaped or triangular cut-away portion' 26 thereafter shifting the This stop pin 3! thus This manual operation, however, is ordinarily employed only in an emergency. Usually the control lever 59 is shifted by admitting pressure fluid to one or the other of the cylinders 23a or 2611 thereby moving the pistons 23 or 24 against the pin iila and shifting the control lever I! from one end portion to the other. This motion is communicated by the pin 25 acting against the corners or ends of the heart-shaped cut-away portion 26 to the gear shift lever l8 and thereby to the gear shift member 14. Thus for a given direction of rotation of the drive shaft 9 the direction of rotation of the driven shaft II can be quickly and easily reversed. At the same time the accidental and unintended shifting of the member l4 and lever l8 are prevented even though a longitudinal force is exerted upon the gear shift member I4.

As previously stated the pin 3| acting in the arcuate slot 30 limits the motion of the lever l8 v and gear shift member M. The longitudinal section shown in Figure 2 illustrates more clearly the arrangement of the stop rod 31 and its actuation by the arm engaging the hollow enlargement 31a.

In the modification shown in Figure 3 the shape of the control lever I9 is alteredso that it bestallations because it gives a compact arrangement which is .well adapted to the very small space available in such vehicles for the gear shifting mechanism.

It will be understood that-I desire to comprehend within my invention such modifications as come within the scope of the claims and the invention. a

Having thus fully described my invention, what I claim as-new and. desire to secure by Letters Patent is:

i. In a shifting mechanism for controlling the shifting of change gearing, a gear shift member, a shift lever engaging said shift member and having a cut-away. portion therein, a control lever swingable about a pivot and having means for engaging said cut-away portion, and means-for swinging said control lever, said cut-away portion having an approximately heart-shaped outline with two oppositely'inclined surfaces, and' said control lever means comprising a pin adapted alternately to engage said oppositely inclined surfaces of said cut-away portion to lock the shift lever, the arcuate portions of said heart-shaped cut-away portion having radii equal to the distance between the center of said pin and the pivot axis of said control lever plus the radius of said pin.

2. In a shifting mechanism for controlling the shifting of the shift member of change gearing, a

' shift lever engaging said shift member and havgear shiftlever 18 and correspondingly moving the gear shift member l4 from one end position to theother. a

The spring device 29 comes into operation to portion 26.

g urge the control lever l9 and its pin 25 into the previously mentioned comers of the cut-away ing a cut-away portion therein with two oppositely inclined locking surfaces, 9. control lever having a locking element for selectively engaging one or the other of said inclined surfaces to lock said shift member in its respective position, said levers being arranged to swing relatively to each otherthrough a mid position in which they are aligned substantially withthe center line connecting the pivots of said levers, and means for "connecting said levers.

swinging said control lever from one looking posi-' tion into another locking position and vice versa, a recess being provided in said cut-away portion intermediate said locking surfaces adapted temporarily to be entered by said locking element while said control lever is being moved from one -locking surface to the other locking surface, .therebyconveying the' movement of said control leverto said shift lever for actuation of-the latter.

3, 'In a shifting mechanism for controlling the shifting of the shift member of change gearing, a pivot member, a shift lever thereon engaging said shift member and having near one end thereof an approximately heart-shaped cut-away portion with two oppositely inclined surfaces, a second pivot member, a control lever thereon having a pinconnected with said control lever and adapted selectively to engage one of said inclined surfaces, and abutment means for limiting the swinging of one of said levers.

' 4. In a shifting mechanism for controlling the shifting of change gearing, a shift member, a shift lever engaging said shift member and having a cut-away portion therein with two oppositely inclined locking surfaces, a control lever having means for selectively engaging one of said'locking surfaces, and yielding means operatively inter- 5. In a shifting mechanism a pivot member, a shift lever thereon engaging said shift member and having an approximately heart-shaped cut-away portion near one end thereof, a second pivot member, a, control lever thereon having a pin engaging the edges of said cut-away portion, and yielding means pivotally attached to and operatively interconnecting said levers.

6. In a shifting mechanism for controlling the shifting of the shift member of change gearing, a shift lever engaging said shift member and having a cut-away portion therein with two. oppositely inclined lockingsurfaces, a control lever having means for selectively engaging one of said inclined surfaces, fluid operable means for shiftfor controlling the shifting of-the shift member of change gearing,

- having a cut-away portiontherein with oppo-- a universal joint connecting said operating rod to said control lever and to said locking means.

9. In a shifting mechanism for controlling the shifting of the shift member of change gearing, a shift lever engaging said shift member and sitely inclined curved surfaces, a control lever having locking means for selectively engaging one of said inclined surfaces and being shiftable about a point constituting the center of curvature of the respective locking surface during its engagement by said locking means, and means for'swinging said control lever, said control lever being T-shaped and said swinging means comprising pistons engaging said T-sha'ped lever and reciprocable in parallel .directions.

10. In a shifting mechanism for controlling the shifting of change gearing, a gear shift. member, a first pivot, a shift lever engaging said gear shift member and adapted to swing about said first pivot for actuating said gear shift member, said shift lever being provided with a heart-shaped cut-away portion having two inclined locking surfaces, a second pivot, a control lever shiftable about said second pivot for actuating said shift lever, and a cylindrical stud con'-. nected with said control lever and adapted alternately to engage one of said inclined surfaces of said shift lever for locking the same, the radius of said stud equalling the maximum change in distance between the axis of the said stud and the axis of said first pivot as'said change occursduring the shift of said stud from one locking surface to the other locking'surface.

11. In a shifting mechanism for controlling the shifting of change gearing, a gear shift member, a shift lever engaging said gear shift member and adapted to shift the same, said shift leverbeing provided with a cut-awayportion having two inclined locking surfaces sepa-','

rated from each other by a semi-circular recess;

. and a control lever shiftable about a pivot and ingsaid control lever, and auxiliary manuallyoperable means adapted likewise to actuate said i control lever.

7. In a shifting mechanism shifting of the shift member of change gearing, a shift lever engaging said shift member and having a cutaway portion therein with two oppositely inclined surfaces, a control lever having means for selectively engaging one of said in.- clined surfaces to lock the shift member in its respective position, a manually operable rod, a-

for controlling the carrying a cylindrical stud adapted alternately to engage one of said surfaces for locking said ing, a pivot member, a shift lever thereon engaging said shift member andhaving near one end thereof an approximately heart-shaped cutaway, portion with two oppositely'inclined suruniversal Joint connecting said operating rod to said control lever so as to allow manual shifting operation of said control lever, and fluid operable means adapted independently of said manually operablerod to eflect a shifting movement ofsaid control lever. I

8. In a shifting mechanism for controlling the shifting of the shift member of change searing,

a shift lever engaging said shift member and havinga cut-away portion therein with two oppositely inclined surfaces, 9. control lever having means for selectively engagin said inclined surfaces, means for locking said control lever in its respective position, a manual operating rod, and

faces separated from each other by a recess, a second pivot member, and a control lever thereon having a pin connected with said control lever and adapted selectively to engage one of said inclined surfaces for establishing a locking engagement between saidshift lever and said control lever, said pin being restricted in its' movement by the side portions of said cut-away portion and being adapted to enter said recess when moved from one inclined surface to the other inclined surface for imparting a shifting movement upon said shift member.

wnnnrsrsuna. 

